A stalwart of the digital photography industry for the past decade, the bridge camera forms a bridge between a compact point-and-shoot camera and a full-blown DSLR.

It typically features some, but not all, of the manual settings and even physical controls that one would expect to find on an entry-level DSLR, including occasional command dials and chunky shooting mode wheels. But it retains some of the accessibility and user friendliness of a snapshot camera, plus the lens can’t be removed or swapped.

Unsurprisingly, its design has aspects of the two types of camera, although the overall look and handling of a bridge camera tends to suggest what we’d term a DSLR ‘lite’.

Nearly every traditional camera manufacturer and electronics giant has a bridge model in its current range. In the case of Fujifilm, to take one example, until the recent launch of its ‘X’ series of high-end compacts, this was the closest the manufacturer got to a more professional camera.

Even now, the Fuji FinePix HS20, Fuji FinePix HS30 has retained the look and feel of a DSLR. These come complete with manual operation of the zoom, a unique feature among bridge models that tend to rely on a button press to prompt the camera to zoom in or out.

Fuji’s manual lens operation arguably enables more precise movement and framing. DSLR-like features such as the ability to shoot unprocessed raw files alongside the JPEG files offered by compact cameras are another feature of most, but not all, bridge cameras.

As well as offering a best of both worlds approach in terms of features and versatility, a distinct advantage of the typical bridge camera is a vastly expanded focal range. In other words, they’ll usually have a longer zoom than you’d find on cameras of more compact proportions. For argument’s sake, let’s say more than the 18x offered by compact travel zooms.

While this means that on a bridge camera just the one lens provides a fantastically broad array of framing options, the other distinctly appealing aspect is the cost.

For example, to match the focal range provided by the likes of Canon’s PowerShot SX40 HS, which offers up to 840mm in 35mm terms, DSLR owners would be looking at spending around £10-£11k on a specialist lens.

This bigger lens also further differentiates bridge cameras from those cameras that have more recently been labelled as premium compacts, such as the Canon PowerShot G12, Nikon P7000 and Fuji X10, which offer DSLR-like solidity, but modest zoom or fixed focal length lenses.

Of course, we couldn’t argue that a bridge camera costing under £400 will match the quality of a DSLR with a mega expensive optic, because of the much smaller sensor size at its core for starters, when compared with the APS-C chip found in entry-level DSLRs. But many amateurs will feel that the bridge camera’s compromise is worth it, because of the broad wealth of framing and capture options at your disposal.

It’s also worth noting that an equivalent lens for a DSLR will be not only expensive, it’ll also be large, heavy and physically unwieldy.

The bridge camera isn’t just more affordable then; it’s a much, much more portable choice. Shoot wide or at the extremes of the camera’s telephoto (maximum zoom) setting – and toggle between them in a matter of seconds – the choice is yours.

It’s perhaps no surprise then that the all-encompassing versatility of today’s bridge camera sees it marketed at families, who might have otherwise been considering an entry-level DSLR, as well as enthusiasts and bird and animal watchers, who will appreciate that extra lens reach without spending a fortune.

This is also why the relative affordability and accessibility of compact system cameras (CSCs), and their interchangeable lenses, has failed to kill off the bridge camera. So the bridge camera isn’t a niche product, but rather a mass market one.

Given the lens power shoehorned onto its compact DSLR-like frame, the bridge camera is also imaginatively known in some circles as a superzoom, mega zoom or power zoom.

How do bridge cameras work?

Bridge cameras work in much the same as any other digital camera that doesn’t use a DSLR-style mirror box mechanism. That’s because bridge cameras have been developed as digital cameras from the get go – not as adaptations of existing 35mm film camera bodies, like the early DSLRs. Even now, DSLRs owe a lot of their handling and performance to analogue SLRs.

While not a professional tool, the bigger piece of glass when compared to the lens on your average pocket camera does arguably provide better quality images from a bridge camera, even if the sensor inside is just as small as your standard point and shooter. So it won’t replace that DSLR just yet.

Like any other dedicated digital camera costing £100 and up, the hub of the bridge camera is a large LCD screen around the back with continuous live view. Depending on the model, it may even be angle-adjustable. This enables formerly tricky low or high-angle shots to be taken, and helps improve visibility by angling the screen away from direct sunlight.

Indeed, bridge cameras were the first to introduce a tilting and swivelling rear monitor, which has over the past two years begun to also feature on CSCs and full DSLRs.

In addition to this screen, on a typical bridge camera there will also be a separate, smaller viewfinder, more recently an electronic viewfinder (EVF), offering a 100% field of view, like the screen.

This eye-level finder is another core bridge camera feature that is steadily finding its way into higher-end compact system cameras around the £1,000 mark. But it’s worth noting that bridge cameras got there first, acting as a test ground for all this new technology.

Aside from that whopper of a lens, a built-in viewfinder is another way a bridge camera now distinguishes itself from your typical pocket point and shoot.

Because of the longer focal range of the zoom lenses on bridge cameras, built-in image stabilisation (IS) – usually optical or sensor-shift rather than the software-enhanced cheat of digital IS – is a must to aid handheld shooting at anywhere near maximum telephoto setting without blur. Gyro motors prompt the sensor to move to counterbalance any external motion.

Such a camera providing all the lens power most casual photographers will ever need sounds alluring. Not everybody wants to have to buy a shed-load of lenses and accessories to get a wide variety of picture-taking options.

The all-in-one ethos of the bridge camera has been further extended in the high-definition era, with most now offering Full HD video capture at cinematic frame rates of 24fps, 25fps or 30fps. Capture commences with the press of a dedicated record button on the backplate or top plate, no matter which other stills shooting mode has been selected on the typically chunky top dial.

The larger body proportions than your average point and shoot also offer more room for stereo microphones, typically placed either side of the lens barrel or directly above. More expensive models offer a vacant hotshoe for the attachment of accessories, including auxiliary flash.

While all bridge cameras enable the use of removable media – SD, SDHC and SDXC cards – some Olympus models also feature integral memory capacity. This has largely died out elsewhere in the market now that affordable removable media is sold in supermarkets.

Which bridge camera to buy?

As always, when buying a bridge camera you’ll have a budget in mind. Fortunately in today’s ultra-competitive market there is a bridge camera available to suit you, especially with the prices of entry-level DSLRs and CSCs falling.

If you’re not bothered about an accessory shoe on your bridge camera, whether the camera records stereo sound and are happy to settle for 1080 x 720p HD video rather than the best quality 1920 x 1080p, then you won’t need to spend top dollar.

If it’s big zooms at a fair price you’re after, then the 35x optical zoom Canon PowerShot SX40 HS is a good place to start your personal investigation of bridge cameras, coming in at a street price of £350-£400.

For those finding the Canon a tad plasticky, there’s the more rugged Fuji FinePix HS20 EXR, an update of 2010′s HS10, or the HS30 model. This offers a 30x optical zoom and the ability to manually adjust the zoom barrel – which is great for enthusiasts looking for that hands-on feel.

Alternatively, Nikon’s rival Coolpix P500 goes ‘one louder’ than the Canon SX40 HS by claiming a 36x optical zoom reach. It doesn’t quite match the Canon at the telephoto end, with an 810mm maximum setting as opposed to 840mm, yet starts wider, at 22.8mm, for those who want to shoehorn group portraits and panoramic landscapes into frame.